Heated capacitor and method of forming the heated capacitor

ABSTRACT

A heated capacitor runs current through either a lower metal plate, an upper metal plate, a lower metal trace that lies adjacent to a lower metal plate, an upper metal trace that lies adjacent to an upper metal plate, or both a lower metal trace that lies adjacent to a lower metal plate and an upper metal trace that lies adjacent to an upper metal plate to generate heat from the resistance to remove moisture from a moisture-sensitive insulating layer.

CROSS REFERENCE TO RELATED APPLICATIONS.

This application is a divisional of U.S. Nonprovisional patentapplication Ser. No. 15/042,319, filed Feb. 12, 2016, which is adivisional of U.S. Nonprovisional patent application Ser. No.14/288,433, filed May 28, 2014 (now U.S. Pat. 9,293,254), the contentsof both of which are herein incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a capacitor and, more particularly, toa heated capacitor and a method of forming the heated capacitor.

2. Description of the Related Art

A capacitor is a well-known electronics device that stores an electriccharge. Capacitors have lower and upper conducting plates which areseparated by an insulating material. A capacitor can be formed on asemiconductor die as a stand-alone structure, or as part of anintegrated circuit.

One common use of capacitors is to protect other electronic circuitsfrom an electric surge that results from an external event. For example,the lower plate of a capacitor can be connected to ground, while theupper plate of the capacitor can be connected to an antenna and an RFfront end so that the capacitor protects the RF front end and associatedcircuitry from a lighting strike to the antenna.

One problem with capacitors that are used to provide protection from anelectric surge that is some insulating materials are sensitive tohumidity, which can significantly degrade the performance of thecapacitor. For example, all polymers, such as polyimide, are sensitiveto moisture, which can reduce the performance of a capacitor from 5,000Vto only 2,000V. Thus, there is a need for an approach to eliminatingmoisture problems.

SUMMARY OF THE INVENTION

The present invention provides a heated capacitor that removes moisturefrom a moisture-sensitive insulating layer. A heated capacitor of thepresent invention includes a first pad, a second pad, a non-conductivelayer, and a first metal structure that touches the non-conductivelayer. The heated capacitor also includes a second metal structure thattouches the non-conductive layer. The second metal structure isconnected to the first pad to receive a first voltage and to a secondpad to receive a second voltage. The first voltage and the secondvoltage are different. The difference between the first voltage and thesecond voltage is to cause a current to flow into, through, and out ofthe second metal structure. The current is to generate heat from aresistance of the second metal structure. The heat is to remove moisturefrom the non-conductive layer.

The present invention also provides a method of forming a heatedcapacitor. The method includes forming a first metal structure, andforming a non-conductive layer that touches the first metal structure.The method also includes forming a second metal structure that touchesthe non-conductive layer, and connecting the first metal structure toreceive a first voltage and a second voltage. The first voltage and thesecond voltage are different. The difference between the first voltageand the second voltage is to cause a current to flow into, through, andout of the first metal structure. The current is to generate heat from aresistance of the first metal structure. The heat is to remove moisturefrom the non-conductive layer.

The present invention further provides an alternate method of forming aheated capacitor. The method includes forming a first metal structure,and forming a non-conductive layer that touches the first metalstructure. The method also includes forming a second metal structurethat touches the non-conductive layer, and connecting the second metalstructure to receive a first voltage and a second voltage. The firstvoltage and the second voltage are different. The difference between thefirst voltage and the second voltage is to cause a current to flow into,through, and out of the second metal structure. The current is togenerate heat from a resistance of the second metal structure. The heatis to remove moisture from the non-conductive layer.

A better understanding of the features and advantages of the presentinvention will be obtained by reference to the following detaileddescription and accompanying drawings which set forth an illustrativeembodiment in which the principals of the invention are utilized.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view illustrating an example of a heatedcapacitor 100 in accordance with the present invention.

FIGS. 2A-2B through 8A-8B are a series of views illustrating a method200 of forming a heated capacitor in accordance with the presentinvention. FIGS. 2A-8A are plan views. FIGS. 2B-8B are cross-sectionalviews taken along lines 2B-2B through 8B-8B of FIGS. 2A-8A,respectively.

FIG. 9 is a cross-sectional view illustrating an example of a heatedcapacitor 900 in accordance with an alternate embodiment of the presentinvention.

FIGS. 10A-10E are views illustrating an example of a heated capacitor1000 in accordance with an alternate embodiment the present invention.FIG. 10A is a plan view. FIG. 10B is a cross-sectional view taken alonglines 10B-10B of FIG. 10A. FIG. 10C is a cross-sectional view takenalong lines 10C-10C of FIG. 10A. FIG. 10D is a plan view taken alonglines 10D-10D of FIG. 10B. FIG. 10E is a plan view taken along lines10E-10E of FIG. 10B.

FIGS. 11A-11E are views illustrating an example of a heated capacitor1100 in accordance with an alternate embodiment the present invention.FIG. 11A is a plan view. FIG. 11B is a cross-sectional view taken alonglines 11B-11B of FIG. 11A. FIG. 11C is a cross-sectional view takenalong lines 11C-11C of FIG. 11A. FIG. 11D is a plan view taken alonglines 11D-11D of FIG. 11B. FIG. 11E is a plan view taken along lines11E-11E of FIG. 11B.

FIGS. 12A-12E are views illustrating an example of a heated capacitor1200 in accordance with an alternate embodiment the present invention.FIG. 12A is a plan view. FIG. 12B is a cross-sectional view taken alonglines 12B-12B of FIG. 12A. FIG. 12C is a cross-sectional view takenalong lines 12C-12C of FIG. 12A. FIG. 12D is a plan view taken alonglines 12D-12D of FIG. 12B. FIG. 12E is a plan view taken along lines12E-12E of FIG. 12B.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a cross-sectional view that illustrates an example of aheated capacitor 100 in accordance with the present invention. Asdescribed in greater detail below, one of the plates of capacitor 100 isutilized as an internal heater to remove moisture from an insulatingmaterial that is sensitive to moisture.

As shown in FIG. 1, heated capacitor 100 includes a non-conductivestructure 110 and a lower metal plate 112 that touches and lies overnon-conductive structure 110. Non-conductive structure 110 can beimplemented with a number of materials, such as silicon dioxide or apolymer like polyimide. Lower metal plate 112 can also be implementedwith a number of materials, such as copper or aluminum.

As further shown in FIG. 1, heated capacitor 100 additionally includes amoisture-sensitive insulating layer 114 that touches and lies over lowermetal plate 112, and an upper metal plate 116 that touches and lies overmoisture-sensitive insulating layer 114. Upper metal plate 116 also liesdirectly over lower metal plate 112. Moisture-sensitive insulating layer114 can be implemented with, for example, a polymer like polyimide.Upper metal plate 116 can be implemented with, for example, copper oraluminum.

In addition, heated capacitor 100 includes a metal via/trace 120 that isconnected to a first side of lower metal plate 112, and a pad 122 thatis connected to metal via/trace 120. Heated capacitor 100 furtherincludes a metal via/trace 124 that is connected to a second side oflower metal plate 112, and a pad 126 that is connected to metalvia/trace 124.

Heated capacitor 100 also includes a number of connecting structures 130that are connected to upper metal plate 116 and the pads 122 and 126. Inthe present example, the connecting structures 130 are illustrated aswires that are bonded to upper metal plate 116 and the pads 122 and 126.Alternately, the connecting structures 130 can be implemented withsolder bumps.

The pads 122 and 126 are electrically connected to external voltagesources by way of the connecting structures 130. Pad 122 is connected toreceive a substantially constant voltage, such as 2V, while pad 126 isconnected to receive a lower substantially constant voltage, such asground. Upper metal plate 116, in turn, is electrically connected to apotential surge source, such as an antenna, and an internal circuit,such as an RF front end, by way of a connecting structure 130.

In operation, when a semiconductor chip that includes heated capacitor100 is powered up, the difference between the voltages on the pads 122and 126 causes a current to flow from pad 122 into, through, and out oflower metal plate 112 to pad 126. Lower metal plate 112, in turn, issized so that the resistance of lower metal plate 112 to the currentflow generates heat that removes moisture from moisture-sensitiveinsulating layer 114. In the event of an electrical surge, lower plate112, moisture-sensitive insulating layer 114, and upper plate 116, whichform a capacitor, function in a conventional manner.

Thus, one of the advantages of heated capacitor 100 is that by removingmoisture from moisture-sensitive insulating layer 114, heated capacitor100 is able to provide increased protection from an electric surge.Another advantage of heated capacitor 100 is that removing moisture frommoisture-sensitive insulating layer 114 can significantly increase thelifetime of the capacitor, by up to 1000×. A further advantage of thepresent invention is that heated capacitor 100 can be formed withoutrequiring the use of any additional masking steps.

FIGS. 2A-2B through 8A-8B show a series of views that illustrate amethod 200 of forming a heated capacitor in accordance with the presentinvention. FIGS. 2A-8A show plan views. FIGS. 2B-8B show cross-sectionalviews taken along lines 2B-2B through 8B-8B of FIGS. 2A-8A,respectively.

As shown in FIGS. 2A-2B, method 200 utilizes a conventionally-formednon-conductive structure 210, and begins by forming a seed layer 212 onnon-conductive structure 210 in a conventional manner. Seed layer 212can be implemented with a layer of titanium (e.g., 300 Å thick) and anoverlying layer of copper (e.g., 3000 Å thick). Next, a mold 214 isformed and patterned on seed layer 212 in a conventional fashion.

As shown in FIGS. 3A-3B, following the formation and patterning of mold214, copper is electroplated in a conventional manner to form a lowermetal plate 216 that touches and lies over non-conductive structure 210.After lower metal plate 216 has been formed, mold 214 is removed,followed by the removal of the underlying regions of seed layer 212.

In the present example, lower metal plate 216 is illustrated as asquare/rectangular shape with two tabs 218 for making via connections.Alternately, other shapes, such as a circular shape, can be used. Inaddition, whichever shape is utilized, the shape can have no tabs or anynumber of tabs.

Following this, as shown in FIGS. 4A-4B, a moisture-sensitive insulatinglayer 220 is deposited on non-conductive structure 210 and lower metalplate 216 in a conventional manner. Moisture-sensitive insulating layer220 can be implemented with, for example, a polymer such as polyimide.

After moisture-sensitive insulating layer 220 has been formed, apatterned photoresist layer 222 is formed on moisture-sensitiveinsulating layer 220. Patterned photoresist layer 222 is formed in aconventional manner, which includes depositing a layer of photoresist,projecting a light through a patterned black/clear glass plate known asa mask to form a patterned image on the layer of photoresist thatsoftens the photoresist regions exposed by the light, and removing thesoftened photoresist regions.

As shown in FIGS. 5A-5B, after patterned photoresist layer 222 has beenformed, the exposed regions of moisture-sensitive insulting layer 220are etched in a conventional fashion to form openings 224 that exposethe top surfaces of the tabs 218 of lower metal plate 216. (When thetabs 218 are omitted, the openings 224 expose the top surface of lowermetal plate 216.) Patterned photoresist layer 222 is then removed in aconventional way, such as with an ash process.

As shown in FIGS. 6A-6B, after patterned photoresist layer 222 has beenremoved, a seed layer 230 is formed on moisture-sensitive insulatinglayer 220 to line the openings 224 and touch the tabs 218 of lower metalplate 216. Seed layer 230 can be implemented with a layer of titanium(e.g., 300 Å thick) and an overlying layer of copper (e.g., 3000 Åthick). Next, a mold 232 is formed and patterned on seed layer 230.

As shown in FIGS. 7A-7B, following the formation and patterning of mold232, copper is electroplated in a conventional fashion to form an uppermetal plate 240 that lies directly above lower metal plate 216. In thepresent example, upper metal plate 240 is illustrated as asquare/rectangular shape. Alternately, other shapes, such as a circularshape, can be used.

The electroplating also forms a first via/trace 242 and a secondvia/trace 244 that are electrically connected to the tabs 218 of lowermetal plate 216. The electroplating further forms a first pad 246 thatis connected to first via/trace 242, and a second pad 248 that isconnected to second via/trace 244.

As shown in FIGS. 8A-8B, after upper metal plate 240, first via/trace242, second via/trace 244, first pad 246, and second pad 248 have beenformed, mold 232 is removed, followed by the removal of the underlyingregions of seed layer 230. The removal of mold 232 and the underlyingregions of seed layer 230 forms a heated capacitor structure 250.

Following this, heated capacitor structure 250 is packaged in aconventional fashion. For example, heated capacitor structure 250 can beattached to a die carrier. After heated capacitor structure 250 has beenattached to the die carrier, a number of connecting structures 252 areconnected to upper metal plate 240, the pads 246 and 248, and the diecarrier.

In the present example, the connecting structures 252 are illustrated aswires that are bonded to upper metal plate 240, the pads 246 and 248,and the die carrier. Alternately, the connecting structures 252 can beimplemented with solder bumps. (Solder bumps are not connected to thedie carrier, but are connected to a printed circuit board.) Heatedcapacitor structure 250 with the connecting structures 252 form a heatedcapacitor 260.

When packaged, first pad 246 is connected to receive a substantiallyconstant voltage, such as 2V, while second pad 248 is connected toreceive a lower substantially constant voltage, such as ground. Further,upper metal plate 240 is connected to a potential surge source, such asan antenna, and an internal circuit, such as an RF front end.

Method 200 can be utilized to realize heated capacitor 100.Non-conductive structure 210 can correspond with non-conductivestructure 110, lower metal plate 216 can correspond with lower metalplate 112, and moisture-sensitive insulating layer 220 can correspondwith moisture-sensitive insulating layer 114. In addition, upper metalplate 240 can correspond with upper metal plate 116, via/trace 242 cancorrespond with via/trace 120, and via/trace 244 can correspond withvia/trace 124. Further, pad 246 can correspond with pad 122, pad 248 cancorrespond with pad 126, and the connecting structures 252 cancorrespond with the connecting structures 130.

FIG. 9 shows a cross-sectional view that illustrates an example of aheated capacitor 900 in accordance with an alternate embodiment thepresent invention. Heated capacitor 900 is similar to heated capacitor100 and, as a result, utilizes the same reference numerals to designatethe structures that are common to both capacitors.

As shown in FIG. 9, heated capacitor 900 differs from heated capacitor100 in that lower metal plate 112 of heated capacitor 900 iselectrically connected to a potential surge source, such as an antenna,and an internal circuit, such as an RF front end, while upper metalplate 116 is electrically connected to the two different externalvoltage sources.

In the present example, lower metal plate 112 is electrically connectedto the potential surge source and the internal circuit by way ofvia/trace 124, pad 126, and a connecting structure 130. (Lower metalplate 112 can alternately be electrically connected to the potentialsurge source and the internal circuit by way of via/trace 120, pad 122,and a connecting structure 130.)

Upper metal plate 116, in turn, is electrically connected to a firstexternal voltage source by way of a connecting structure 130 to receivea substantially constant voltage, such as 2V, and to a second externalvoltage source by way of a connecting structure 130 to receive a lowersubstantially constant voltage, such as ground.

Heated capacitor 900 operates the same as heated capacitor 100,differing only in which capacitor plate provides the heat and whichcapacitor plate is connected to the potential surge source and theinternal circuit. In addition, heated capacitor 900 is formed in thesame manner as heated capacitor 260, except that one tab, one via/trace,and one pad are no longer required. For example, the formations of theleft-side tab 218, via/trace 242, and pad 246 can be omitted.

FIGS. 10A-10E show views that illustrate an example of a heatedcapacitor 1000 in accordance with an alternate embodiment the presentinvention. FIG. 10A shows a plan view. FIG. 10B shows a cross-sectionalview taken along lines 10B-10B of FIG. 10A. FIG. 10C shows across-sectional view taken along lines 10C-10C of FIG. 10A. FIG. 10Dshows a plan view taken along lines 10D-10D of FIG. 10B. FIG. 10E showsa plan view taken along lines 10E-10E of FIG. 10B.

Heated capacitor 1000 is similar to heated capacitor 260 and, as aresult, utilizes the same reference numerals to designate the structuresthat are common to both capacitors. As shown in FIGS. 10A-10E, heatedcapacitor 1000 differs from heated capacitor 260 in that heatedcapacitor 1000 generates heat by running a current through a lower metalline that lies laterally adjacent to the lower metal plate.

In the present example, as shown in FIGS. 10B and 10D, heated capacitor1000 differs from heated capacitor 260 in that heated capacitor 1000utilizes a lower metal plate 1010 in lieu of lower metal plate 216.Lower metal plate 1010 has a sidewall 1012 that extends around theperiphery of lower metal plate 1010.

As shown in FIGS. 10B, 10C, and 10D, lower metal plate 1010 is the sameas lower metal plate 216, except that lower metal plate 1010 has only asingle tab 1014 for making a via connection. Although lower metal plate1010 is illustrated as a square/rectangular shape, other shapes, such asa circular shape, can alternately be used. In addition, whichever shapeis utilized, the shape can have no tabs or multiple tabs.

As shown in FIGS. 10B, 10C, and 10D, heated capacitor 1000 also differsfrom heated capacitor 260 in that heated capacitor 1000 includes a lowermetal trace 1020 that lies laterally adjacent to lower metal plate 1010.In one embodiment, no metal structure lies laterally between lower metalplate 1010 and lower metal trace 1020. In another embodiment, a metalstructure can lie laterally between lower metal plate 1010 and lowermetal trace 1020.

In the present example, lower metal trace 1020 partially surrounds lowermetal plate 1010. As a result, lower metal trace 1020 lies adjacent tohalf of sidewall 1012 of lower metal plate 1010, as well as tothree-quarters and more than three-quarters of sidewall 1012 of lowermetal plate 1010.

As shown in FIGS. 10A, 10C, and 10E, heated capacitor 1000 additionallydiffers from heated capacitor 260 in that heated capacitor 1000 includesa via/trace 1022 that is attached to one end of lower metal trace 1020,and a pad 1024 that is attached to via/trace 1022. Heated capacitor 1000also includes a via/trace 1026 that is attached to an opposite end oflower metal trace 1020, and a pad 1028 that is attached to via/trace1026.

Further, in the present example, lower metal plate 1010 is electricallyconnected to an external voltage source to receive a substantiallyconstant voltage, such as ground, by way of via/trace 242, pad 246, anda connecting structure 252. (Alternately, lower metal plate 1010 can beelectrically connected to the potential surge source and the internalcircuit by way of via/trace 242, pad 246, and a connecting structure252.)

Upper metal plate 240, in turn, is connected to the potential surgesource and the internal circuit by way of a connecting structure 252.(Alternately, upper metal plate 240 can be connected to an externalvoltage source to carry a substantially constant voltage, such asground, by way of a connecting structure 252.)

In operation, when a semiconductor chip that includes heated capacitor1000 is powered up, the difference between the voltages on the pads 1024and 1028 causes a current to flow from pad 1024 into, through, and outof lower metal trace 1020 to pad 1028. Lower metal trace 1020, in turn,is sized so that the resistance of lower metal trace 1020 to the currentflow generates heat that removes moisture from moisture-sensitiveinsulating layer 220. In the event of an electrical surge, lower plate1010, moisture-sensitive insulating layer 220, and upper plate 240,which form a capacitor, function in a conventional manner. Thus, unlikeheated capacitors 100 and 260, no current flows through lower metalplate 1010.

Heated capacitor 1000 is formed in the same manner as heated capacitor260. For example, lower metal plate 1010 can be formed at the same timeand the same manner as lower metal plate 216, except that one tab can beomitted. In addition, lower metal trace 1020 can be formed at the sametime and the same manner as lower metal plate 216 by modifying mold 214.Further, via/trace 1022, pad 1024, via/trace 1026, and pad 1028 can beformed at the same time and in the same manner as via/trace 242 and pad246.

FIGS. 11A-11E show views that illustrate an example of a heatedcapacitor 1100 in accordance with an alternate embodiment the presentinvention. FIG. 11A shows a plan view. FIG. 11B shows a cross-sectionalview taken along lines 11B-11B of FIG. 11A. FIG. 11C shows across-sectional view taken along lines 11C-11C of FIG. 11A. FIG. 11Dshows a plan view taken along lines 11D-11D of FIG. 11B. FIG. 11E showsa plan view taken along lines 11E-11E of FIG. 11B.

Heated capacitor 1100 is similar to heated capacitor 1000 and, as aresult, utilizes the same reference numerals to designate the structuresthat are common to both capacitors. As shown in FIGS. 11A-11E, heatedcapacitor 1100 differs from heated capacitor 1000 in that heatedcapacitor 1100 generates heat by running currents through both a lowermetal line that lies laterally adjacent to lower metal plate 1010, andan upper metal line that lies laterally adjacent to upper metal plate240.

As shown in FIGS. 11A, 11B, and 11C, heated capacitor 1100 differs fromheated capacitor 1000 in that heated capacitor 1100 includes an uppermetal trace 1110 that lies laterally adjacent to upper metal plate 240.In one embodiment, no metal structure lies laterally between upper metalplate 240 and upper metal trace 1110. In another embodiment, a metalstructure can lie laterally between upper metal plate 240 and uppermetal trace 1110.

Upper metal plate 240 has a sidewall 1112 that extends around theperiphery of upper metal plate 240. In the present example, upper metaltrace 1110 partially surrounds upper metal plate 240. As a result, uppermetal trace 1110 lies adjacent to half of sidewall 1112 of upper metalplate 240, as well as to three-quarters and more than three-quarters ofsidewall 1112 of upper metal plate 1110.

As shown in FIGS. 11A, 11C, and 11E, heated capacitor 1100 has threevia/traces 242, 1022, and 1026 that extend up from the lower level. Asshown in FIGS. 11A and 11C, heated capacitor 1100 additionally differsfrom heated capacitor 1000 in that heated capacitor 1100 includes a pad1120 that is attached to one end of upper metal trace 1110, and a pad1122 that is attached to an opposite end of upper metal trace 1110.

The pads 1120 and 1122 are electrically connected to external voltagesources by way of the connecting structures 252. Pad 1120 is connectedto receive a substantially constant voltage, such as 2V, while pad 1122is connected to receive a lower substantially constant voltage, such asground. Pads 1024 and 1120 can be connected to equal or differentvoltages. Similarly, pads 1028 and 1122 can be connected to equal ordifferent voltages.

In operation, when a semiconductor chip that includes heated capacitor1100 is powered up, the difference between the voltages on the pads 1024and 1028 causes a current to flow from pad 1024 into, through, and outof lower metal trace 1020 to pad 1028. Lower metal trace 1020, in turn,is sized so that the resistance of lower metal trace 1020 to the currentflow generates heat that removes moisture from moisture-sensitiveinsulating layer 220.

In addition, the difference between the voltages on the pads 1120 and1122 causes a current to flow from pad 1120 into, through, and out ofupper metal trace 1110 to pad 1122. Upper metal trace 1110, in turn, issized so that the resistance of upper metal trace 1110 to the currentflow generates heat that removes moisture from moisture-sensitiveinsulating layer 220. In the event of an electrical surge, lower plate1010, moisture-sensitive insulating layer 220, and upper plate 240,which form a capacitor, function in a conventional manner.

Heated capacitor 1100 is formed in the same manner as heated capacitor1000. For example, upper metal trace 1110, pad 1120, and pad 1122 can beformed at the same time and the same manner as upper metal plate 240,via/trace 242, pad 246, via/trace 1022, pad 1024, via/trace 1026, andpad 1028 by modifying mold 232.

FIGS. 12A-12E show views that illustrate an example of a heatedcapacitor 1200 in accordance with an alternate embodiment the presentinvention. FIG. 12A shows a plan view. FIG. 12B shows a cross-sectionalview taken along lines 12B-12B of FIG. 12A. FIG. 12C shows across-sectional view taken along lines 12C-12C of FIG. 12A. FIG. 12Dshows a plan view taken along lines 12D-12D of FIG. 12B. FIG. 12E showsa plan view taken along lines 12E-12E of FIG. 12B.

Heated capacitor 1200 is similar to heated capacitor 1100 and, as aresult, utilizes the same reference numerals to designate the structuresthat are common to both capacitors. As shown in FIGS. 12A-12E, heatedcapacitor 1200 differs from heated capacitor 1100 in that heatedcapacitor 1200 generates heat by running a current through only uppermetal trace 1110. As a result, lower metal trace 1020, via/trace 1022,via/trace 1026, pad 1024, and pad 1028 are omitted.

In operation, when a semiconductor chip that includes heated capacitor1200 is powered up, the difference between the voltages on the pads 1120and 1122 causes a current to flow from pad 1120 into, through, and outof upper metal trace 1110 to pad 1122. Upper metal trace 1110, in turn,is sized so that the resistance of upper metal trace 1110 to the currentflow generates heat that removes moisture from moisture-sensitiveinsulating layer 220.

In the event of an electrical surge, lower metal plate 1010,moisture-sensitive insulating layer 220, and upper metal plate 240,which form a capacitor, function in a conventional manner. Heatedcapacitor 1100 is formed in the same manner as heated capacitor 1100,except that the modifications required to form lower metal trace 1020,via/trace 1022, via/trace 1026, pad 1024, and pad 1028 are omitted.

It should be understood that the above descriptions are examples of thepresent invention, and that various alternatives of the inventiondescribed herein may be employed in practicing the invention. Thus, itis intended that the following claims define the scope of the inventionand that structures and methods within the scope of these claims andtheir equivalents be covered thereby.

What is claimed is:
 1. A heated capacitor comprising: a first pad; asecond pad; a non-conductive layer; a first metal structure that touchesthe non-conductive layer; a second metal structure that touches thenon-conductive layer; and a heater of the heated capacitor, the heaterincluding a first connection between the second metal structure and thefirst pad and a second connection between the second metal structure andthe second pad, wherein the first metal structure lies directly abovethe second metal structure, and the non-conductive layer lies betweenthe first and second metal structures.
 2. The heated capacitor of claim1, wherein the non-conductive layer includes a polymer.
 3. The heatedcapacitor of claim 1, wherein the non-conductive layer comprisespolymide.
 4. The heated capacitor of claim 1, wherein the first metalstructure comprises copper.
 5. The heated capacitor of claim 1, whereinthe first metal structure comprises aluminum.
 6. The heated capacitor ofclaim 1, wherein the second metal structure comprises copper.
 7. Theheated capacitor of claim 1, wherein the second metal structurecomprises aluminum.
 8. The heated capacitor of claim 1, the second metalstructure being connected to the first pad to receive a first voltageand the second pad to receive a second voltage, the first voltage andthe second voltage being different, the difference between the firstvoltage and the second voltage to cause a current to flow into, through,and out of the second metal structure, the current to generate heat froma resistance of the second metal structure, the heat to remove moisturefrom the non-conductive layer.
 9. The heated capacitor of claim 1,further comprising: a first bond wire connected to the first pad; asecond bond wire connected to the second pad; and a third bond wireconnected to the first metal structure.
 10. A heated capacitorcomprising: a first pad; a second pad; a non-conductive layer; a firstmetal structure that touches the non-conductive layer; a second metalstructure that touches the non-conductive layer; and a heater of theheated capacitor, the heater including a first connection between thesecond metal structure and the first pad and a second connection betweenthe second metal structure and the second pad, wherein the first metalstructure lies directly below the second metal structure, and thenon-conductive layer lies between the first and second metal structures.11. The heated capacitor of claim 10, wherein the non-conductive layerincludes a polymer.
 12. The heated capacitor of claim 10, wherein thenon-conductive layer comprises polymide.
 13. The heated capacitor ofclaim 10, wherein the first metal structure comprises copper.
 14. Theheated capacitor of claim 10, wherein the first metal structurecomprises aluminum.
 15. The heated capacitor of claim 10, wherein thesecond metal structure comprises copper.
 16. The heated capacitor ofclaim 10, wherein the second metal structure comprises aluminum.
 17. Theheated capacitor of claim 10, the second metal structure being connectedto the first pad to receive a first voltage and the second pad toreceive a second voltage, the first voltage and the second voltage beingdifferent, the difference between the first voltage and the secondvoltage to cause a current to flow into, through, and out of the secondmetal structure, the current to generate heat from a resistance of thesecond metal structure, the heat to remove moisture from thenon-conductive layer.
 18. A heated capacitor comprising: a first pad; asecond pad; a non-conductive layer comprising polymide; a first metalstructure that touches the non-conductive layer; a second metalstructure that touches the non-conductive layer; a first connectionbetween a first end of the second metal structure and the first pad anda second connection between a second end of the second metal structureand the second pad, wherein the first metal structure lies directlyabove the second metal structure, and the non-conductive layer liesbetween the first and second metal structures; a first bond wireconnected to the first pad; a second bond wire connected to the secondpad; and a third bond wire connected to the first metal structure. 19.The heated capacitor of claim 18, wherein the first metal structure andthe second metal structure comprises copper.
 20. The heated capacitor ofclaim 18, wherein the first metal structure and the second metalstructure comprises aluminum.